Cells

functions of cells

covering, movement, storage, lining, connection, defense, communication, reproduction

covering

epidermal cells

lining

epithelial cells

storage

adipocytes

movement

muscle cells

connection

collegen

defense

white blood cells

communication

neurons

reproduction

stem cells

structure of plasma membrane and the common characteristics

• Lipids: Phospholipids in bi-layer w/ their hydrophilic (love water) heads pointing to extracellular and intracellular on the other lateral and their hydrophobic (fear water) tails pointing towards each other

• Cholesterol

• Glycolipids

• Proteins

• Integral and peripheral

What are protein channels and their function

Integral proteins that form a channel that specific materials can go through to enter or exit the cell

Type types of transport proteins

Channel proteins (ions, water), carrier proteins: (sugar like glucose)

Active transport

Requires ATP energy and moves materials against their concentration gradient from low to high concentration

Passive transport

Does not require ATP energy, no extra energy required, and moves materials down or with their concentration gradient from high to low concentration

Types of passive transport

• Simple diffusion: high to low concentration until equilibrium is reached

• Osmosis: movement of water from high to low concentration

• Facilitated diffusion: need transport proteins to help the diffusion of large particles or particles that are insoluble in lipids

• Bulk filtration: diffusion of solvents and solutes together

Types of active transport

• ion pumps: move into across membrane

• Bulk transport: exocytosis - large molecules transported out of the cell

• Endocytosis: large molecules taken into the cell

• Phagocytosis: engulfs particles

• Pinocytosis: takes in droplets of fluid, receptor mediated

• Endocytosis: movement of specific molecules into the cell by specific receptors

Isotonic

The concentration of the solute inside the cell and outside the cell is the same

Hypertonic

The concentration of the solute outside of the cell is greater than the concentration of the solute inside the cell, water will leave the cell and crenation will take place

Hypotonic

The concentration of the solute outside the cell is less than the concentration of the solute inside the cell, water will enter the cell and lysis will take place

Interphase

• cell grows to a certain size and divides to form two new daughter cells

• Period of preparation to divide: G1 (gap) phase: cell growth, organelle duplicate. S (Synthesis) phase: DNA replication. G2 (gap) Phase: cell growth, organelles duplicated

Mitosis

• division of cell’s nuclear parts

• Prophase: chromosomes become visible, each chromosome contains two identical portions (chromatids), attached at the centromere, centrioles replicate, move to opposite end of cell, nuclear envelope and nucleus break up and disappear, microtubules are assembled spindle forms

Metaphase

• chromosomes line up at the equator, spindle fibers join centromere

Anaphase

• centromeres are pulled apart, chromatids separate → separate chromosomes, chromosomes migrate to opposite ends

Telophase

• chromosomes unwind into chromatin, nuclear envelope forms, nucleolus reappears, spindle microtubules disassemble

Cytokinesis

• division of cell’s cytoplasm, cleavage furrow